Embodiments of the invention relate to fin boxes for watercraft, such as surfboards, paddle boards, boats and other aquatic devices. Some particular embodiments of the invention relate to fin boxes that can be used with more than one type of fin attachment mechanism.
Many surfboards, paddle boards, boats and other aquatic devices (referred to generically below as “watercraft”) have one or more fins that improve directional stability and control of the watercraft. For example, some watercraft have a single fin at the rear of the watercraft that is sometimes referred to as a “center fin” or a “skeg”. In addition to or instead of a center fin, some watercraft may have one or more pairs of fins mounted near the edge (or “rail”) of the watercraft that are commonly referred to as “rail fins”. Rail fins are typically positioned at an angle such that the leading edge of each rail fin is oriented toward the centerline of the watercraft.
One or more of the fins employed in some watercraft can be removable enabling the user of the watercraft to change the size and/or shape of the fins to change the way the watercraft moves through the water. For example, when surfing larger waves a particular surfer may want a relatively large fin while the same surfer may prefer a smaller fin when surfing smaller waves. Fins typically attach to a fin box that is embedded in the watercraft. For example, FIG. 1A is a simplified illustration depicting a bottom surface 104 of a surfboard 100 with removable fins, while FIGS. 1B and 1C are simplified side and rear plan views of surfboard 100. As shown in the figures, surfboard 100 includes a body 102 and three fins 110, 112 and 114. Fin 110 is a center fin while fins 112 and 114 are rail fins. Center fin 110 is attached to body 102 through a first fin box 120, while rail fins 112 and 114 are attached to body 102 through fin boxes 122 and 124, respectively.
A surfer may want to replace fin 110 with a different sized or shaped fin and can do so by removing the fin 110 from its respective fin box 120 and attaching a new fin to the fin box. Generally fin 110 has an attachment mechanism formed in a base of the fin that is specifically designed to enable the fin to be inserted into and secured to its respective fin box 120. Thus, fin 110 and fin box 120 are part of a fin box system and are specifically designed to be used together. Unfortunately, different manufacturers of fins may use different proprietary attachment systems. Thus, a first fin made by one manufacturer sometimes cannot be replaced on a particular surfboard with a second fin made by a different manufacturer as the attachment mechanism for the second fin may not be compatible with the fin box designed for use with the first fin. For example, two fin box systems commonly included in surfboards are made by FCS and Futures. Fins designed for the FCS fin box are not compatible with fins designed for the Futures fin box. Similarly, fins designed for the Futures fin box are not compatible with fins designed for the FCS fin box.
Some fin boxes have been developed that accept fins from different fin box systems, but each has limitations that make them less than ideal.